$(20pts)A$ bar measuring $h_{\text{g}\text{r}\text{o}\text{s}\text{s}}=24mm$ wide with two $r=4mm$ semicircular grooves by $t=12mm$

thick. The tensile load on the bar is $P=1300N.$

$(4$ pts$)$ Calculate $h_{\text{n}\text{e}\text{t}}[mm]$

$(4$ pts$)$ Calculate the ratio $\frac{r}{h_{\text{n}\text{e}\text{t}}}[$unitless$]$

$(4$ pts$)$ Mark the value of $K$ from the graph, and write down the approximate value $[$unitless$]$

$(4$ pts$)$ Calculate the net cross$-$sectional area $A_{\text{n}\text{e}\text{t}}[m{m}^2]$

$(4$ pts$)$ Calculate the maximum stress using ${}_{\text{m}\text{a}\text{x}}[MPa]$